refactor(git): simplify git commit message generation task

Remove requirements for atomic commits and multiple commit handling to make
the commit message generation process more straightforward. Update
markdown formatting to use bold instead of backticks.

Author: yingmanwumen

lua/plugins/ai/codecompanion/slash_commands/git_commit.lua

@@ -28,8 +28,8 @@ local function generate_commit_message()
   local content = [[Tools allowed to use: @cmd_runner @files
 - Task:
   1. Before proceeding, review the changes. If there're potential issues or typos, stop and state them. You should fully understand every piece of code in diffs, and analyze the purpose and context of each change.
-  2. Write commit messages for the diffs with `commitizen convention`. Format as a gitcommit code block. Keep the commit messages concise and precise. "Concise" means keep the title under 50 characters and wrap message at 72 characters. Remember, you should ensure that each commit is atomic, means each commit only contains ONE logical change, and you should write multiple commits for multiple logical changes.
-  3. After generating commit messages, stage diffs and then commit them with `git commit -F- <<EOF`. Multiple commit messages should be committed separately, and you should stage the corresponding diffs carefully.
+  2. Write commit message for the diffs with **commitizen convention**. Format as a gitcommit code block. Keep the commit message concise and precise. "Concise" means keep the title under 50 characters and wrap message at 72 characters.
+  3. After generating commit message, stage diffs and then commit them with `git commit -F- <<EOF`.
 
 Full diffs are as follows: